<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <a href="www.baidu.com" style="display: block; width: 100px; height: 200px;">asdasdasdasdasdasdas</a>
</body>
<script>
    var a=1;
    var b=2;
    var c;
    c=a;
    a=b;
    b=c;
    console.log(a,b);

    // var b =prompt("请输入0-59")
    // if(b<59&&b>=10)
    // alert(b);
    // else if(b<10&&b>0)
    // alert('0'+b)

    var a=prompt("0-59")
    a>0&&a<10?alert('0'+a):alert(a);
    
</script>
</html>